Seed meter

ABSTRACT

A seed meter for an agricultural planter in which the seed disc is rotatably mounted within a seed meter housing. As the seed disc rotates, the apertures in the disc rotate along a seed aperture path through a horizontally adjacent seed pool area. The seed disc includes cavities disposed along the seed aperture path to agitate the seeds in the seed pool area. A singulator having multiple co-planar singulator surfaces is biased against the seed side surface of the seed disc.

CROSS-REFERENCE TO RELATED APPLICATIONS

This applications claims the benefit of U.S. Provisional Application No.61/466,047, filed Mar. 22, 2011.

BACKGROUND

In recent years, growers of corn and other crops have come to recognizethe importance of planting individual seeds at the appropriate spacingdue to increased seed and crop input prices, but also because they havethe ability to monitor the economic impact of skips, doubles ormisplaced seeds using modern planter monitors. For these reasons modernseed meters have been developed that include features which improve thesingulation of seeds. However, each added feature increases the amountof time that the grower must spend replacing wear parts or making otheradjustments prior to or during planting operations. Due to weather andother factors, the available time to plant corn and other crops is oftenextremely limited, with each planter required to cover hundreds of acreswhile limited in speed due to reduced seed meter performance at higherplanting speeds.

Thus, there is a need for a seed meter having improved singulation andseed spacing capability at higher speeds and which is also easilyrepairable and modifiable.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a side elevation view of a single row unit of aconventional row crop planter.

FIG. 2 is a perspective view of an embodiment of a seed meter.

FIG. 3 is a partial perspective view of an embodiment of a seed meter.

FIG. 4 is another partial perspective view of an embodiment of a seedmeter.

FIG. 5 is a partial side elevation view of an embodiment of a seedmeter.

FIG. 6 is another partial perspective view of an embodiment of a seedmeter.

FIG. 7 is another partial perspective view of an embodiment of a seedmeter.

FIG. 8 is another side elevation view of an embodiment of a seed meter.

FIG. 9 is another side elevation view of an embodiment of a seed meter.

FIG. 10 is a partial side elevation view of an embodiment of a seedmeter.

FIG. 11 is a partial side elevation view of an embodiment of a seedmeter.

FIG. 12A is a perspective view of an embodiment of a seed singulator andan embodiment of an axial spring.

FIG. 12B is another perspective view of an embodiment of a seedsingulator and an embodiment of an axial spring.

FIG. 12C is another perspective view of an embodiment of a seedsingulator and an embodiment of an axial spring.

FIG. 12D is another perspective view of an embodiment of a seedsingulator and an embodiment of an axial spring.

FIG. 13A is another perspective view of an embodiment of a seed meter.

FIG. 13B is another partial perspective view of an embodiment of a seedmeter.

FIG. 13C is a partial perspective view of an embodiment of a seed meter.

FIG. 14 is a perspective view of a seed disc, vacuum seal and anembodiment of an ejector wheel assembly.

FIG. 15 is a perspective view of a vacuum cover, a vacuum seal, and anembodiment of an ejector wheel assembly.

FIG. 16 is a perspective view of a vacuum cover and vacuum seal.

FIG. 17A is a perspective view of an embodiment of an ejector wheelassembly.

FIG. 17B is a side elevation view of an embodiment of an ejector wheelassembly.

FIG. 18A is a side elevation view of another embodiment of a seed discand another embodiment of an ejector wheel assembly.

FIG. 18B is a side elevation view of an embodiment of a seed disc and anembodiment of an ejector wheel assembly.

FIG. 18C is a side elevation view of an embodiment of an ejector wheel.

FIG. 18D is a top view of an embodiment of an ejector wheel.

FIG. 19A is a partial side elevation view of an embodiment of seed disc.

FIG. 19B is a cross-sectional view of a seed disc along the section X-Xof FIG. 19A.

FIG. 19C is a partial perspective view of an embodiment of a seed disc.

FIG. 20A is a partial side elevation view of another embodiment of aseed disc.

FIG. 20B is a cross-sectional view of a seed disc along the section Y-Yof FIG. 20A.

FIG. 20C is a cross-sectional view of a seed disc along the section Z-Zof FIG. 20B.

FIG. 20D is a perspective view of an embodiment of a seed disc.

DESCRIPTION

Referring now to the drawings, wherein like reference numerals designateidentical or corresponding parts throughout the several views, FIG. 1illustrates a single row unit 10 of a conventional row crop planter. Asis well known in the art, the row units 10 are mounted in spacedrelation along the length of a transverse toolbar 12 by a parallellinkage 14 which permits each row unit 10 to move verticallyindependently of the toolbar and the other spaced row units in order toaccommodate changes in terrain or upon the row unit encountering a rockor other obstruction as the planter is drawn through the field. Each rowunit 10 includes a frame 16 which operably supports a seed hopper 18, afurrow opening assembly 20, a seed meter 100, a seed tube 46 and afurrow closing assembly 50.

The furrow opening assembly 20 comprises a pair of furrow opening discs22 which are rotatably mounted on shafts 26 secured to a shank 30comprising a part of the row unit frame 16. The furrow opening assembly20 further comprises a pair of gauge wheels 32 rotatably supported bygauge wheel arms 35 also secured to the frame 16. As the planter isdrawn through the field, the rotating furrow opening discs 22 cut aV-shaped furrow 40 through the soil surface 36. The egress end of theseed tube 46 is disposed between the rearwardly diverging furrow openingdiscs 22.

In operation, as the planter is drawn through the field along thedirection of travel as indicated by the arrow 38, the seed hopper 18communicates a constant supply of seeds 42 to the seed meter 100. Theseed meter 100 meters or dispenses individual or “singulated” seeds 42at regularly spaced intervals into the seed tube 46. The seed tube 46directs the seeds downwardly and rearwardly between the diverging furrowopening discs 22 before depositing the seeds into the V-shaped furrow40. The seeds are then covered with soil by the furrow closing assembly50. A seed sensor 60 detects the passage of seeds through the seed tube46 as is known in the art.

Novel Seed Meter Embodiments

Embodiments of a novel seed meter 100 are illustrated in FIGS. 2-20.Referring to FIGS. 2 and 3, the seed meter 100 includes a housingcomprised of a vacuum cover 110 and a seed housing 105. As describedfurther herein, the seed meter 100 functions by selecting one seed at atime from seeds communicated into the seed housing 105 and dispensingeach seed through the seed exit 180. A vacuum inlet 115 is coupled tothe vacuum cover 110. Vacuum hoses or tubes (not shown) connect thevacuum inlet 115 to a vacuum source (not shown) such as a vacuumimpeller.

The seed housing 105 includes pivots 113 (FIG. 3) and tabs 103 (FIG. 2).When assembled, the tabs 103 extend through holes in the vacuum cover110 such that retaining springs 108 may be biased against pivots 113 andtabs 103 to retain the seed housing 105 in position against the vacuumcover 110.

Referring to FIG. 3, the seed meter 100 is shown with the vacuum cover110 and other components removed for clarity. A shaft 183 is rotatablycoupled to bearings 184. Bearings 184 are held in place by the vacuumcover 110. A drive plate 186 is coupled to and rotates with the shaft183. Drive plate 186 is releasably coupled to a seed disc 120. Seed disc120 includes apertures 122 and preferably includes drive teeth 121. Inoperation, the seed disc 120 may be rotated by a driven gear (not shown)coupled to drive teeth 121 (as described further herein) or by a drivenshaft (not shown) coupled to an adapter 185 (FIG. 2) mounted to theshaft 183.

Turning to FIG. 4, the interior of the seed housing 105 is shown withthe seed disc 120, drive shaft 183 and drive plate 186 removed. A brush112 is mounted to seed housing 105 such that its bristles contact theseed-side surface of the seed disc 120. A singulator 130 is mounted tothe seed housing 105 (as described further herein) which cooperates withthe seed disc 120 to singulate the seeds before they are dispensedthrough the seed exit 180. The singulator preferably includes multiplesingulator surfaces in contact with a seed side surface 140 of the seeddisc 140.

Referring to FIGS. 5, 6, and 13A-C, seeds are communicated into the seedmeter 100 beneath a baffle 160 mounted to the seed housing 105. A seedpool area 150 (FIG. 5) is disposed horizontally adjacent to the seeddisc 120 near a bottom end of the seed housing 105 for collection ofseeds communicated into the seed meter.

The height of baffle 160 may be adjusted along guides 164 and 166. Thebaffle 160 is mounted to the seed housing 105 by rivet 162, whichextends outside the seed housing 105 (as best seen in FIGS. 9 and 13C)and may be moved vertically by the operator along a notched slot 117without disassembling the housing. Each notch in slot 117 is sized tohold the rivet 162 in place such that the operator can select the heightof baffle 160 by pushing the rivet up and down. As illustrated, visualindicators (e.g., numbers 1 through 4) are preferably located adjacentto the notches for positioning the rivet 162 at corresponding heights ofthe baffle 160 for ease of reference.

Removable Floating Singulator Embodiments

Referring to FIGS. 6-8, the singulator 130 is releasably mounted to theseed housing 105 so as to bias the singulator against the seed disc 120while allowing the singulator to “float” both axially and longitudinallywith respect to the axis of rotation of the seed disc. The singulator isreleasably coupled to an axial spring 137 by attachment ears 139. Theaxial spring 137 is preferably made of a material (e.g., spring steel)which is elastically deformable. The axial spring 137 is mounted tobosses 142. The bosses 142 are sized such that the singulator 130 isbiased against the face of the seed disc 120 when the seed disc is inits normal position. Thus, when the seed disc 120 is deflected axiallyaway from the vacuum cover 110, the tension in axial spring 137increases, allowing the singulator to remain in contact with the seeddisc without interfering with the rotation of the seed disc. Likewise,when the seed disc is deflected axially toward the vacuum cover 110, thetension in axial spring 137 decreases such that the singulator remainsin contact with the seed disc.

Radial spring 111 is mounted to the seed housing 105 such that inoperation, the radial spring biases the singulator radially against theseed disc 120 when the seed disc is in its normal position.

Referring to FIGS. 12A-D, the singulator 130 is illustrated in detailattached to the axial spring 137. The singulator 130 includes base 133,arms 136, upper lobe plate 134 and lower lobe plate 132. The upper lobeplate 134 includes three singulation lobes, while the lower lobe plate132 includes two singulation lobes. In operation, attachment ears 139grasp the base 133. When the axial spring 137 is attached to thesingulator 130, the attachment ears 139 extend past and away from thebase 133 and are easily manipulated and deflected. It should beappreciated that other configurations of the singulator 130 could beused to achieve the objectives described herein.

It should be appreciated that the singulator 130 is easily replaceablewith another singulator with a different lobe configuration fordifferent seeds or if it is necessary to replace the singular due towear on the singulator lobes. The singulator 130 is removable by pullingit away from the axial spring 137 with sufficient force that theattachment ears 139 deflect away from each other sufficiently to releasethe base 133. The attachment ears 139 may also be deflected away fromeach other with one hand while pulling the singulator 130 away from theaxial spring 137 with the other. Likewise, the singulator 130 may bereplaced by pressing the base 133 of the singulator between theattachment ears 139 with sufficient force to cause the attachment earsto deflect away from each other to allow the base of the singulator topass between them. To replace the singulator, the base 133 may be pushedbetween the ears causing them to deflect away from one another beforereturning to the normal position in which the base of the singulator isagain secured between the ears. In this way the singulator 130 may beeasily removed and replaced by hand without the use of tools and withoutremoving or changing the location of axial spring 137, which remains inthe correct location to bias the singulator 130 against the seed disc120 while allowing the singulator 130 to “float” with deflections ordeformations of the seed disc.

Referring to FIGS. 10 and 11, the seed meter 100 is illustrated with theseed housing 105 and other components removed so that the singulator 130may be seen in its preferred location biased against the seed-sidesurface 140 of the seed disc 120. The seed-side surface 140 ispreferably normal to the axis of rotation of the seed disc 120. Theseed-side surface 140 is also preferably substantially flat with theexception of cavities 128, described in more detail later. For clarity,only the upper and lower lobe plates 132 and 134 are shown in FIG. 11.In operation, the seed disc 120 rotates in the direction indicated byarrow 129 such that the seed apertures 122 travel along a seed aperturepath. A portion of the seed aperture path is adjacent to the seed poolarea 150. As the seed apertures 122 turn past the seed pool area 150 atthe bottom of the seed housing 105, a vacuum side of each seed apertureis placed in fluid communication with the vacuum source such that one ormore seeds 42 become entrained over apertures 122. As the seed-bearingapertures rotate between the upper and lower lobe plates 132,134, thelobes of the lobe plates bump, rotate and position the seeds so thatonly one seed is firmly entrained over the aperture while the otherseeds drop back into the seed pool 150, thereby leaving one seed peraperture. After the apertures 122 rotate past the 3 o'clock position asviewed in FIG. 11, the apertures 122 are no longer in communication withthe vacuum source resulting in the seeds being released from theapertures and falling into the seed exit 180.

Referring to FIGS. 14-16, the vacuum cover 110 includes a continuousmounting groove into which a vacuum seal 190 is press fit. In operation,the vacuum seal 190 is pressed against the vacuum-side of the seed disc120 and the interior of the vacuum seal is in communication with thevacuum inlet 115 (FIG. 1) such that as the apertures 122 rotate past theperimeter of the vacuum seal 190 toward its interior they are placed influid communication with the vacuum source.

Removable Seed Ejector Assemblies

It has been found that seeds or partial seeds may become lodged in theseed apertures 122 and remain there even after the apertures 122 passoutside of the vacuum seal 190 where no vacuum is imposed. This isundesirable because when the apertures re-enter the seed reservoir anadditional seed may not be entrained in an aperture holding a seed orpartial seed. Thus, referring again to FIGS. 14-16, a seed ejectorassembly 170 is preferably mounted to the vacuum cover 110. The seedejector assembly 170 includes a shaft 174, a mounting clip 172, a leverarm 175 and an ejector wheel 176 having plungers 177. The ejector wheel176 is rotatably coupled to the lever arm 175. The lever arm isrotatably coupled to the shaft 174. The shaft is rotatably receivedwithin the mounting clip 172. As best seen in FIG. 15, the mounting clip172 is attached to a mounting port 179, which is preferably formedintegrally with the vacuum cover 110. As best seen in FIG. 14, as theseed disc 120 rotates, the ejector wheel 176 rotates and the plungers177 enter each seed aperture 122, knocking out any seeds, partial seedsor debris in the seed apertures from the back side or vacuum-side of theseed disc 120.

As best illustrated in FIGS. 14 and 15, a spring 171 is preferablydisposed between the lever arm 175 and the vacuum cover 110. The spring171 has a first end held in place at a first end by a knob 173 on thelever arm 175 and has a second end held in place by cavity 192 in thevacuum cover 110. It should be appreciated that the spring 171 biasesthe ejector wheel 176 against the disc and allows the seed ejectorassembly 170 to “float” with deflections or deformations of the seeddisc 120.

It should be appreciated that the user may wish to remove the seedejector assembly 170 or replace it due to wear on the ejector wheel 176,to install a differently configured seed ejector assembly, or for otherreasons. As illustrated in FIGS. 16, 17A and 17B, the mounting clip 172may be easily removed from and reattached to the mounting port 179without the use of tools. The mounting port 179 includes apertures 196and a tab 195. Mounting clip 172 includes rigid hooks 197 and resilienthook 198. During installation, the user first inserts rigid hooks 197into apertures 196, then preferably presses mounting clip 172 againstvacuum cover 110 such that resilient hook 198 deflects around tab 195and returns to a relaxed state secured around tab 195. It should beappreciated that in addition to deflection of resilient hook 198 withrespect to mounting clip 172, the mounting clip 172 also preferablydeflects to allow resilient hook 198 to deflect around the tab 195.After attachment, the mounting clip 172 is secured against mounting port179 until the user removes the mounting clip by bending the mountingclip to release the resilient hook 198 from tab 195 and then moving therigid hooks 197 free of the apertures 196.

Alternative Ejector Wheel and Disc Embodiments

Turning to FIGS. 18A-18D, a modified seed ejector assembly 270 isillustrated in cooperation with a modified seed disc 220. The seed disc220 includes an array 224 of apertures 222. The seed disc 220 furtherincludes an array 234 of guide cavities 232. The guide cavity array 234is preferably substantially concentric with the seed aperture array 224.

The seed ejector assembly 270 includes a lever arm 275. The lever arm275 is preferably pivotally biased toward the seed disc 220 as describedherein with respect to the lever arm 175. As best illustrated in FIG.18B, the seed ejector assembly 270 also includes an ejector wheel 276pivotally mounted to the lever arm 275 and a guide wheel 286 pivotallymounted to the lever arm 275. Continuing to refer to FIG. 18B, theejector wheel 276 and the guide wheel 286 are preferably pivotallymounted to the lever arm by a retaining pin 272 extending throughcentral apertures in the ejector wheel and guide wheel. The retainingpin 272 preferably allows the ejector wheel 276 and the guide wheel totranslate slightly toward and away from the lever arm 275 such that theejector wheel and guide wheel are allowed to translate radially towardand away from the center of the seed disc 220. As best illustrated inFIGS. 18C and 18D, the ejector wheel 276 includes radially arrangedplungers 278 and the guide wheel 286 includes radially arranged guideteeth 288. The seed ejector assembly preferably includes more guideteeth 288 than plungers 278, and preferably includes three guide teethper plunger. The ejector wheel 276 is preferably fixed to the guidewheel 286 such that the ejector wheel is constrained to rotatesynchronously with the guide wheel. Each plunger 278 is preferablyaligned with one of the guide teeth 288. For example, as shown in FIG.18D, the upper and lower plungers 278 are aligned with upper and lowerguide teeth along a plane A1 and the left and right plungers 278 arealigned with left and right guide teeth along a plane A2.

In some embodiments of the ejector wheel 276, the plungers 278 includetips 277. In some embodiments of the seed disc 220, the apertures 222are tapered to small openings 223 (FIG. 18A). The tips 277 arepreferably sized to fit within the small openings 223. It should beappreciated that in such embodiments, more precise alignment of theejector wheel 276 with respect to the seed disc 220 is necessary inorder to knock seeds or debris from the small openings 223 withoutinterference between the ejector wheel and seed disc.

In operation, as the disc rotates, the guide teeth 288 sequentiallyengage the guide cavities 232. The plungers 278 sequentially engage theseed apertures 222. Referring to FIG. 18A, the guide cavity array 234 isaligned with the seed aperture array 224 such that each seed aperture222 is aligned with a guide cavity 232 along a plane (e.g., plane A3)intersecting the center of the seed disc 220. It should be appreciatedthat guide teeth 288 engage guide cavities 232 when the plungers 278 arenot engaging the seed apertures 222, thus moving the ejector wheel 286to the proper angular position to successfully engage each seedaperture. Additionally, it should be appreciated that as the ejectorwheel translates with respect to the retaining pin 272, the guide teeth232 likewise retain the ejector wheel 286 at the proper radial distancefrom the center of the seed disc 220 such that the ejector wheel cansuccessfully engage each seed aperture 222.

Seed Disc Cavities

Referring to FIGS. 19A-19C, the seed disc 120 preferably includes seeddisc cavities 128 disposed near the radial edge of the seed disc. Thecavities 128 are preferably disposed to pass adjacent to the seed poolarea 150. Each cavity 128 is preferably disposed forward of an adjacentseed aperture 122 along the direction of travel of the seed aperturepath. The cavities 128 are preferably disposed between each pair of seedapertures 122. Seed apertures 122 are preferably substantially normal tothe surface 140 of the seed disc 120; i.e., a central axis of each seedaperture 122 is preferably substantially normal to the surface 140 ofthe seed disc 120. Raised surfaces 123 with respect to the bottom of theassociated cavity 128 are preferably disposed between each aperture 122and the adjacent cavity 128. The upper surface of the raised surfaces123 are preferably co-planar with the surface 140 of the seed disc 120.

Each cavity 128 preferably comprises an agitation cavity sized toagitate the seeds in the seed pool area 150. Thus the cavities 128 arepreferably sized to allow significant movement of seeds 42 into and outof the cavities as each cavity moves adjacent to the seed pool 150. Theouter perimeter of the cavity 128 is preferably larger than the outerperimeter of the adjacent seed aperture 122. The area of an intersectionbetween the surface 140 of the seed disc 120 and each cavity 128 ispreferably greater than the area of an intersection between the surface140 and each seed aperture 122. It should be appreciated that each seedaperture is sized to allow limited movement of seeds 42 into the seedaperture. Moreover, the cavities 128 are preferably wider than theaverage size of seeds 42 to be planted using the seed disc 120.Moreover, the depth D (FIG. 19B) of the cavities 128 is preferablygreater than 0.05 inches.

Referring to FIG. 10 in combination with FIG. 19, each cavity 128preferably has an inner sidewall 242 and an outer sidewall 240 locatedat distances Ri, Ro respectively from the center C (i.e., the central orrotational axis) of the disc. The difference between the radii Ro and Riis preferably greater than the diameter of the seed apertures 122. Theradius Ro is preferably larger than the distance between the seedaperture and the center of the seed disc 120. The radius Ro ispreferably larger than the radius Ra between a distal end of said seedaperture 122 and the center of the disc 120.

In operation, as the seed disc 120 rotates through the seed pool area150 located to the side of the seed disc (as best illustrated in FIG.11), seeds move in and out of the cavities 128 such that the seed poolis stirred or agitated. This agitation improves the successful loadingof seeds on the seed apertures 122, particularly at relatively highplanting speeds which correspond to faster seed disc rotation speeds.

Each cavity 128 preferably includes a sidewall 124 oriented to face theseed pool area 150 as the cavity rotates into the seed pool area. Thesidewall 124 is preferably substantially vertical (FIG. 19B), i.e.,substantially normal to the surface 140 of the seed disc 120. As viewedalong the rotational axis of the seed disc (FIG. 19A), the sidewall 124is preferably curved, and preferably is semicircular. In operation, thesidewalls 124 sequentially enter the seed pool area 150 and push theseeds such that the seed pool is stirred and agitated.

The cavities 128 preferably include a bevel 126 oriented to face awayfrom the seed pool as the disc 120 rotates into the seed pool area 150.An angle A (FIG. 19B) between bevel 126 and the surface 140 of the seeddisc 120 is preferably between 15 and 35 degrees with respect to thesurface of the disc. In operation, when seeds are released from the disc(at approximately the 3 o'clock position on the view of FIG. 11), seedsoccasionally fall toward the disc and into the cavity 128 located belowthe seed aperture 122. In such instances, the seed bounces or slidesagainst the bevel 126, smoothly transitioning the seed back out of thecavity 128 and increasing consistency between seed fall times.

Although a seed disc 120 is disclosed herein including series of seedapertures 122 and cavities 128 having the same radial distance from thecenter of the seed disc, other embodiments include rows of seed cavities

Referring to FIGS. 20A-20D, an alternative seed disc 320 is illustratedhaving cavities 328 disposed between seed apertures 322. Each cavity 328preferably includes vertical sidewalls 324 and bevels 326. Each cavity328 preferably includes a beveled inner sidewall 342 and a beveled outersidewall 340. The beveled sidewalls 342, 340 reduce the interior volumeof the cavity 328 and allow seeds to smoothly transition out of thecavity 328 while the seeds are being agitated in the seed pool area 150.Thus each beveled sidewall 342, 340 discourages entrapment of seeds inthe cavities 328, particularly smaller seed varieties.

Although the various improvements described herein are illustrated withrespect to a vacuum-type seed meter, they would be equally applicable toother seed singulating meters, including positive-air meters such asthat disclosed in U.S. Pat. No. 4,450,979 to Deckler, incorporatedherein in its entirety by reference.

The foregoing description is presented to enable one of ordinary skillin the art to make and use the invention and is provided in the contextof a patent application and its requirements. Various modifications tothe preferred embodiment of the apparatus, and the general principlesand features of the system and methods described herein will be readilyapparent to those of skill in the art. Thus, the present invention isnot to be limited to the embodiments of the apparatus, system andmethods described above and illustrated in the drawing figures, but isto be accorded the widest scope consistent with the spirit and scope ofthe appended claims.

1. A seed meter for an agricultural planter, comprising: a meter housingincluding a seed housing; an opening for communicating seeds into saidseed housing; a seed pool area for collection of said seeds disposednear a bottom end of said housing; and a seed disc rotatably mountedwithin said meter housing, said seed disc being disposed horizontallyadjacent to said seed pool area, said seed disc further including a seedaperture, said seed aperture disposed to rotate along a seed aperturepath, a portion of said seed aperture path being adjacent to said seedpool area, said seed disc further having a cavity disposed along saidseed aperture path, wherein said cavity has an outer perimeter largerthan an outer perimeter of said seed aperture.
 2. The seed meter ofclaim 1, wherein said cavity comprises an agitation cavity sized toallow said seeds in said seed pool area to move substantially into saidcavity such that said cavity substantially agitates the seeds in saidseed pool area.
 3. The seed meter of claim 2, wherein said cavityincludes a substantially vertical sidewall, said sidewall oriented toface said seed pool area as said cavity enters said seed pool area. 4.The seed meter of claim 1, wherein a distal end of said seed aperture isdisposed at a first radial distance from a center of said seed disc, andwherein said cavity includes an outer sidewall disposed at a secondradial distance from said center of said seed disc, and wherein saidsecond radial distance is larger than said first radial distance.
 5. Theseed meter of claim 4, wherein said cavity includes an inner sidewalldisposed at a third radial distance from said center of said seed disc,and wherein said third radial distance is smaller than said first radialdistance.
 6. The seed meter of claim 1, wherein an area of anintersection between a surface of said seed disc and said cavity isgreater than the area of an intersection between said surface and saidseed aperture.
 7. The seed meter of claim 1, wherein said cavityincludes a bevel, said bevel oriented to face away from said seed poolarea as said cavity becomes adjacent to said seed pool area.
 8. The seedmeter of claim 1, wherein said seed disc further includes a raisedsurface disposed between said cavity and said seed aperture.
 9. The seedmeter of claim 2, wherein said seed disc further includes a raisedsurface disposed between said cavity and said seed aperture.
 10. Theseed meter of claim 1, wherein said cavity is wider than the seeds inthe seed pool along a plane normal to said seed disc, wherein said planeintersects a central axis of said seed disc.
 11. A seed meter for anagricultural planter, comprising: a meter housing including a seedhousing; an opening for communicating seeds into said housing; a seedpool area for collection of said seeds disposed near a bottom end ofsaid housing; a seed disc rotatably mounted within said meter housing,said seed disc having a substantially flat seed side surface, said seeddisc being located to the side of said seed pool area; and a singulatorhaving multiple singulator surfaces, said singulator surfaces beingcoplanar, said singulator surfaces contacting said seed side surface,wherein said seed disc includes at least four seed apertures disposed torotate along a seed aperture path, a portion of said seed aperture pathbeing adjacent to said seed pool area, and wherein said seed discfurther includes at least four cavities, each of said cavities disposedalong said seed aperture path and sized to allow seeds in said seed poolarea to substantially enter said cavities.
 12. The seed meter of claim11, wherein each of said cavities includes a first sidewall oriented toface said seed pool area as each of said cavities enters said seed poolarea, said first sidewall being substantially normal to the seed sidesurface of said disc.
 13. The seed meter of claim 12, wherein said firstsidewall is curved.
 14. The seed meter of claim 12, further including araised surface disposed between said first sidewall and one of said seedapertures.
 15. The seed meter of claim 14, wherein said raised surfaceis substantially co-planar with said seed side surface.
 16. A method ofplanting seeds, comprising: communicating seeds into a seed housing;collecting said seeds in a seed pool within said seed housing; moving aseed disc cavity adjacent to said seed pool such that some of said seedspass into and out of said seed disc cavity; moving a seed aperturehaving a seed side and a vacuum side along a seed aperture path, aportion of said seed aperture path being adjacent to said seed pool,said seed aperture path intersecting said seed disc cavity, said seeddisc cavity having a larger outer perimeter than an outer perimeter ofsaid seed aperture; placing said vacuum side of said seed aperture influid communication with a vacuum source while said seed aperture is insaid seed pool; entraining a first seed on said seed side of said seedaperture; and removing said vacuum side of said seed aperture from fluidcommunication with said vacuum source to release said first seed fromsaid seed side.
 17. The method of claim 16, wherein said seed disccavity comprises an agitation cavity sufficiently deep and wide to allowseeds to move substantially into said seed disc cavity.
 18. The methodof claim 17, wherein said seed disc cavity includes a first sidewalladjacent to said seed aperture, and further including the step ofpushing at least one seed in said seed pool with said first sidewall.19. The method of claim 18, wherein at least a portion of said firstsidewall is substantially normal to a surface of said seed disc.
 20. Themethod of claim 17, wherein said seed disc cavity includes a bevel, saidbevel disposed downstream of said seed aperture along said seed aperturepath, said bevel facing said seed aperture, and further including thestep of contacting said bevel with said first seed after said first seedis released from said seed aperture.